Quantifying the Impact of Competition and Spatial Heterogeneity on the Structure and Dynamics of a Four-Species Guild of Winter Annuals

1996 ◽  
Vol 147 (1) ◽  
pp. 1-32 ◽  
Author(s):  
Mark Rees ◽  
Peter J. Grubb ◽  
Dave Kelly
Keyword(s):  
Spatial Heterogeneity ◽  
Structure And Dynamics ◽  
Winter Annuals ◽  
The Impact ◽  
Species Guild

The impact of high hydrostatic pressure on structure and dynamics of β-lactoglobulin

2013 ◽  
Vol 1830 (10) ◽  
pp. 4974-4980 ◽  
Author(s):  
Daniela Russo ◽  
Maria Grazia Ortore ◽  
Francesco Spinozzi ◽  
Paolo Mariani ◽  
Camille Loupiac ◽  
...  
Keyword(s):  
Hydrostatic Pressure ◽  
High Hydrostatic Pressure ◽  
Structure And Dynamics ◽  
The Impact ◽  
Β Lactoglobulin

scholarly journals Probing the Influence of Multiscale Heterogeneity on Effective Properties of Graphite Electrodes

2021 ◽  
Author(s):  
Chance A. Norris ◽  
Mukul Parmananda ◽  
Scott Alan Roberts ◽  
Partha P. Mukherjee
Keyword(s):  
Spatial Heterogeneity ◽  
Transport Properties ◽  
Effective Properties ◽  
Lithium Ion ◽  
Particle Morphology ◽  
Electrochemical Characteristics ◽  
Pore Scale ◽  
Structural Anisotropy ◽  
Graphite Electrodes ◽  
The Impact

Graphite electrodes in the lithium-ion battery exhibit various particle shapes, including spherical and platelet morphologies, which influence structural and electrochemical characteristics. It is well established that porous structures exhibit spatial heterogeneity, and particle morphology can influence transport properties. The impact of particle morphology on the heterogeneity and anisotropy of geometric and transport properties has not been previously studied. This study characterizes the spatial heterogeneities of eighteen graphite electrodes at multiple length scales by calculating and comparing structural anisotropy, geometric quantities, and transport properties (pore-scale tortuosity and electrical conductivity). We found that particle morphology and structural anisotropy play an integral role in determining the spatial heterogeneity of directional tortuosity and its dependency on pore-scale heterogeneity. Our analysis reveals that the magnitude of in-plane and through-plane tortuosity difference influences the multiscale heterogeneity in graphite electrodes.

scholarly journals Hepatocellular carcinoma: Intratumoral EpCAM-positive cancer stem cell heterogeneity identifies high-risk tumor subtype

2020 ◽  
Author(s):  
Jenny Krause ◽  
Johann von Felden ◽  
Christian Casar ◽  
Thorben W. Fründt ◽  
Johanna Galaski ◽  
...  
Keyword(s):  
Hepatocellular Carcinoma ◽  
High Risk ◽  
Spatial Heterogeneity ◽  
Early Recurrence ◽  
Epcam Expression ◽  
Clinical Endpoints ◽  
Time To Recurrence ◽  
Dismal Prognosis ◽  
The Impact ◽  
Intratumoral Distribution

Abstract Background: The translational interest in the intratumoral heterogeneity of hepatocellular carcinoma (HCC) has been increasing. The dismal prognosis of this pathology is linked to the features of the HCC harbouring cancer stem cells (CSC), represented by EpCAM-expression. However, the extent of the impact of intratumoral distribution of CSC-features, both on the recurrence after curative resection and on clinical outcome, remains unknown. To address this, we investigated the spatial heterogeneity of CSC-features with the aim of identifying the unique HCC patient subgroups amenable to adjuvant treatment.Methods: We designed a tissue microarray (TMA) from patients who had received liver resection between 2011 and 2017. Tumor specimens were sampled at multiple locations (n=3-8). EpCAM-positivity was assessed for intensity and proportion by applying a score dividing three groups: (i) negative (E-/-); (ii) heterogeneous (E-/+); and (iii) homogeneous (E+/+). The groups were further analysed with regard to time-to-recurrence (TTR) and recurrence-free-survival (RFS).Results: We included 314 tumor spots from 69 patients (76.8% male, median age 66 years, liver cirrhosis/fibrosis 75.8). The risk factors were alcohol abuse (26.2%), NASH (13.1%), HBV (15.5%), HCV (17.9%) and others (27.4%), representative of a typical Western cohort. E+/+ patients experienced significantly shorter TTR and RFS compared to E+/- (and E-/-) patients (TTR 5 vs. 19 months, p=0.022; RFS 5 vs. 14 vs. 21 months, p=0.016). Only homogeneous EpCAM-positivity correlated with higher AFP levels (>400 ng/ml, p=0.031).Conclusions: Spatial heterogeneity of EpCAM-expression was markedly present in the cohort. Of note, only homogeneous EpCAM-expression correlated significantly with early recurrence, whereas heterogeneous EpCAM-expression was associated with clinical endpoints comparable to EpCAM-negativity. We identified a unique HCC subtype associated with a high risk of tumor recurrence.

scholarly journals Assessment of Effect of Hydropower Plant Projects on Socio-Environmental Sustenance and Development in Rwanda: A Review Done At Rubagabaga Hydropower Ltd.

2022 ◽  
Vol 10 (01) ◽  
pp. 2888-2904
Author(s):  
Dr. MUTESI Jean Claude
Keyword(s):  
Community Structure ◽  
Null Hypothesis ◽  
Quantitative Research ◽  
Target Population ◽  
Positive Influence ◽  
Hydropower Plant ◽  
P Value ◽  
Structure And Dynamics ◽  
Hydropower Plants ◽  
The Impact

The study investigated the socio-economic and environmental impact of hydropower projects in Rwanda with a case study of Rubagabaga hydropower Ltd operating from Nyabihu District. It examines the impact of a socio-economic and environmental hydropower plant in Rwanda, identifies the challenge hydropower plants face in Rwanda, and finally investigates the relationship between hydro powers and their socio-economic impact in Rwanda? In this research, the quantitative research design is based on statistical data of the research that was used with quantitative and qualitative methods. Questionnaires were used to collect data. The target population of this study was made up of 252 participants including 154 respondents all from ten different villages surrounding the Rubagabaga plant in Nyabihu District. Data were analyzed using descriptive and correlation analysis and tables that were interpreted to confirm or deny the relevance of the main and specific objectives. Based on results from table no.16 demonstrates that the beta= 0.397 with the t value of 2.333 and the p-value of 0. 021. Since the p-value is less than 0.05, the researcher rejected the null hypothesis and considered it an alternate. There is a strong positive relationship between environmental assessment of hydropower plant projects and socio-environmental sustenance and development. In a nutshell, the researcher has rejected the null hypothesis and considered its alternate. Community structure and dynamics have a positive influence on socio-environmental sustenance and development. Table no.16 shows that beta= 0.341 with the t value of 2.668 as the p-value was 0.009. Since the p-value is less than 0.05. Therefore, the researcher rejected the null hypothesis and considered it an alternate. According to table no.21, the changes in community structure and dynamics of the hydropower plant project cause the increase of 0.341 (34.1%) of the socio-environment sustenance and development. The ratio of beta modal results for the t value expressed t=2.66 hence the probability value is significant on socio-environment sustenance and development noting that sig. =0.009. Carefully, the researcher has rejected the null hypothesis and considered its alternate. With this in mind, community structure and dynamics has a positive influence on socio-environmental sustenance and development. Table no.16 has shown beta= 0.478 with the t value of 4.543 as the p-value was 0.000 which is less than 0.05. According to the findings, the changes in government policies, stability, and support of hydropower plant project causes the increase of 0.478 (47.80%) of the socio-environment sustenance and development. The ratio of beta modal results for the t value expressed t= 4.54 hence the probability value is significant on socio-environment sustenance and development noting that sig. =0.000.

scholarly journals Environmental Regulation for Transfer of Pollution-Intensive Industries: Evidence From Chinese Provinces

2020 ◽  
Vol 8 ◽  
Author(s):  
Weiqing Li ◽  
Huaping Sun ◽  
Yunsu Du ◽  
Ziyao Li ◽  
Farhad Taghizadeh-Hesary
Keyword(s):  
Spatial Heterogeneity ◽  
Environmental Regulation ◽  
Economic Effect ◽  
Clean Energy ◽  
Industrial Sector ◽  
Promoting Effect ◽  
Industrial Transfer ◽  
Theoretical Mechanism ◽  
Threshold Regression Model ◽  
The Impact

How environmental regulations affect the transfer of pollution-intensive industries is the core issue of balanced regional development and pollution reduction in China. This paper analyses the theoretical mechanism of the impact of environmental regulation on industrial transfer based on the distinction between formal environmental regulation and informal environmental regulation. To this aim, the paper selects panel data of 30 provinces in China from 2008 to 2018 and uses the fixed effect econometric model to test the impact of environmental regulation on the transfer of pollution-intensive industries, then uses a threshold regression model to study the threshold characteristics and spatial heterogeneity of environmental regulation on pollution-intensive industrial transfer. The results show a significant inverted U-shaped relationship between formal environmental regulation and the transfer of pollution-intensive industries. The increase of formal environmental regulation intensity affects restraining and then promoting the transfer out of pollution-intensive industries. The promoting effect also shows the characteristics of first increasing and then decreasing, verifying that there are threshold characteristics and spatial heterogeneity. Overall, informal environmental regulation promotes the transfer of pollution-intensive industries and shows the informal regulation’s economic effect. The paper then puts forward the corresponding policy suggestions, including utilizing clean energy-saving technologies in the industrial sector, which is incredibly significant to realize the coordinated development of environmental protection and economy.

scholarly journals The impact of wind field spatial heterogeneity and variability on short-term wind power forecast errors

2019 ◽  
Vol 11 (3) ◽  
pp. 033304 ◽  
Author(s):  
Mao Yang ◽  
Luobin Zhang ◽  
Yang Cui ◽  
Qiongqiong Yang ◽  
Binyang Huang
Keyword(s):  
Spatial Heterogeneity ◽  
Wind Power ◽  
Wind Field ◽  
Forecast Errors ◽  
Short Term ◽  
Wind Power Forecast ◽  
The Impact

scholarly journals Evaluating the impact of spatial resolution on tropospheric NO<sub>2</sub> column comparisons within urban areas using high-resolution airborne data

2019 ◽  
Vol 12 (11) ◽  
pp. 6091-6111 ◽  
Author(s):  
Laura M. Judd ◽  
Jassim A. Al-Saadi ◽  
Scott J. Janz ◽  
Matthew G. Kowalewski ◽  
R. Bradley Pierce ◽  
...  
Keyword(s):  
High Resolution ◽  
Los Angeles ◽  
Spatial Heterogeneity ◽  
Spatial Resolution ◽  
Urban Areas ◽  
High Temporal Resolution ◽  
Ozone Monitoring Instrument ◽  
Vertical Column ◽  
Monitoring Instrument ◽  
The Impact

Abstract. NASA deployed the GeoTASO airborne UV–visible spectrometer in May–June 2017 to produce high-resolution (approximately 250 m×250 m) gapless NO2 datasets over the western shore of Lake Michigan and over the Los Angeles Basin. The results collected show that the airborne tropospheric vertical column retrievals compare well with ground-based Pandora spectrometer column NO2 observations (r2=0.91 and slope of 1.03). Apparent disagreements between the two measurements can be sensitive to the coincidence criteria and are often associated with large local variability, including rapid temporal changes and spatial heterogeneity that may be observed differently by the sunward-viewing Pandora observations. The gapless mapping strategy executed during the 2017 GeoTASO flights provides data suitable for averaging to coarser areal resolutions to simulate satellite retrievals. As simulated satellite pixel area increases to values typical of TEMPO (Tropospheric Emissions: Monitoring Pollution), TROPOMI (TROPOspheric Monitoring Instrument), and OMI (Ozone Monitoring Instrument), the agreement with Pandora measurements degraded, particularly for the most polluted columns as localized large pollution enhancements observed by Pandora and GeoTASO are spatially averaged with nearby less-polluted locations within the larger area representative of the satellite spatial resolutions (aircraft-to-Pandora slope: TEMPO scale =0.88; TROPOMI scale =0.77; OMI scale =0.57). In these two regions, Pandora and TEMPO or TROPOMI have the potential to compare well at least up to pollution scales of 30×1015 molecules cm−2. Two publicly available OMI tropospheric NO2 retrievals are found to be biased low with respect to these Pandora observations. However, the agreement improves when higher-resolution a priori inputs are used for the tropospheric air mass factor calculation (NASA V3 standard product slope =0.18 and Berkeley High Resolution product slope =0.30). Overall, this work explores best practices for satellite validation strategies with Pandora direct-sun observations by showing the sensitivity to product spatial resolution and demonstrating how the high-spatial-resolution NO2 data retrieved from airborne spectrometers, such as GeoTASO, can be used with high-temporal-resolution ground-based column observations to evaluate the influence of spatial heterogeneity on validation results.

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